<template>
  <div class="todo-footer">
    <label>
      <input type="checkbox" :checked="isAll" @click="checkAll($event.target.checked)"/>
    </label>
    <span> <span>已完成{{doneTotal}}</span> / 全部{{total}} </span>
    <button class="btn btn-danger" @click="clearDoneTodo">清除已完成任务</button>
  </div>
</template>

<script>
export default {
  name: "Footer",
	props:['todos','clearDoneTodo','checkAll'],
	computed: {
		// 已完成的总数
		doneTotal(){
			//思路一
			return this.todos.filter(t => t.done).length

			//思路二
			/* let n = 0
			this.todos.forEach((item) => {
				if(item.done === true){
					n++
				}
			});
			return n */
		},
		// 总数
		total(){
			return this.todos.length
		},
		// 是否全选
		isAll(){
			return this.todos.every( t => t.done ) && this.todos.length > 0
		}
	},
	/* methods:{
		handleCheckAll(e){
			// console.log(e.target.checked)
			this.checkAll(e.target.checked)
		}
	} */
};
</script>

<style scoped>
	/*footer*/
	.todo-footer {
		height: 40px;
		line-height: 40px;
		padding-left: 6px;
		margin-top: 5px;
	}
	.todo-footer label {
		display: inline-block;
		margin-right: 20px;
		cursor: pointer;
	}
	.todo-footer label input {
		position: relative;
		top: -1px;
		vertical-align: middle;
		margin-right: 5px;
	}
	.todo-footer button {
		float: right;
		margin-top: 5px;
	}
</style>